Communications systems having higher data throughput and greater efficiency in the use of available bandwidth increasingly are in demand. In, illustratively, a satellite communications system, a satellite provides a plurality of communications channels to terrestrial receivers. Each communications channel has associated with it, for example, a particular transponder, a particular polarization and the like. Normally, each defined channel broadcasts at its maximum data rate.
Where the amount of data to be transmitted is less than the amount of data that a channel is capable of transmitting, the defined channel is underutilized. In this case, the defined channel transmits NULL packets during those time slices within which there is no data available to be transmitted. Where the data to be transmitted requires more bandwidth than is available on the channel, an alternate channel having greater available capacity must be selected. Thus, communications channels typically operate at less than a 100% utilization level due to the likelihood that the number of data streams to be transmitted, and the amount of data within each stream, are likely not to match the bandwidth available in the transmission channels.